1. Join Now

    AVForums.com uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Please explain Scaling?

Discussion in 'LCD & LED LCD TVs' started by jimg, Dec 16, 2004.

  1. jimg

    jimg
    Member

    Joined:
    Jul 4, 2004
    Messages:
    826
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    31
    Ratings:
    +58
    I am very pleased with my Sharp 37GA4E and am wondering about DVI input.
    At the moment I have my old DVD player connected via component and PQ is good, but am thinking of buying a new Denon 1910 with DVI.
    Can some one explain this scaling business?
    The screen is 768 pixels high, so presumably the internal electronics scale the input up to this resolution? If so, what happens when you feed 720p through DVI? Does that mean it gets scaled again, from 720 to 768, or am I missing something here? It sounds a real mess and do you really get any improvement as the detail is not there in the first place, or is just because you have stayed in the digital domain?
    A short lesson from some one you understands this would be useful :lease:

    Cheers
    Jim
     
  2. jgrg

    jgrg
    Active Member

    Joined:
    Oct 19, 2004
    Messages:
    547
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    28
    Location:
    Cambridge
    Ratings:
    +33
    Yes, 720p will get scaled again to 768 lines by the display. I don't expect that this will introduce many artifacts, but I intend to test this with my Denon DVD3910 (which I already have) and my Sharp LC32GA4E (if it ever arrives). The Sharp will allow me to switch between screen filling and dot-for-dot on the DVI input. If it does introduce artifacts I will consider buying a DVDO iScan HD+, and get top quality scaling from my Sky digibox too.

    I am expecting the DVI input to be better because keeping it digital removes the guess-work of converting the analogue input from the DVD player back to digital. You should get smoother shading from one colour to another, eliminating some of the posterisation effect you can get on LCDs.

    James
     
  3. Alan D

    Alan D
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    720p gets scaled to 768 on some displays, although not on Philips LCDs - they leave it at the native 720 - which is why it has a border around it . So you get a pixel matched picture, which looks excellent, but slightly smaller than full panel size. I get around this by using 1080i and 576p into my Philips, which is scaled to 768 in both cases - and does not seem to introduce any noticable artifacts.
     
  4. Yaka

    Yaka
    Active Member

    Joined:
    Dec 20, 2000
    Messages:
    1,682
    Products Owned:
    2
    Products Wanted:
    0
    Trophy Points:
    63
    Ratings:
    +115
    Sorry to jump on to some one elses thread, but if i got say the 32A4gE ot tosh 32LW48 would i get a better pic quality if conected my ntl digtal box to the I Scan HD+ ?
     
  5. ianh64

    ianh64
    Active Member

    Joined:
    Aug 7, 2004
    Messages:
    2,233
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    51
    Location:
    SW London/Surrey borders
    Ratings:
    +63
    The answer to this depends on what component is best at performing the deinterlacing and scaling, source, scaler or display. However in the case of the IScan, I would say that there would be an improvement in quality.

    I sometimes scale Freeview output through my DVD player (which can scale external sources too) and get excellent results, but since my display, a Loewe Xelos SL, handles freeview with very good results, I generally don't bother unless I am watching in surround sound.

    -Ian
     
  6. jimg

    jimg
    Member

    Joined:
    Jul 4, 2004
    Messages:
    826
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    31
    Ratings:
    +58
    Ianh64,
    Which DVD player does that? Can you fed it SKy thru a RGB Scart connection and scale that?
    Cheers
    JimG
     
  7. Yaka

    Yaka
    Active Member

    Joined:
    Dec 20, 2000
    Messages:
    1,682
    Products Owned:
    2
    Products Wanted:
    0
    Trophy Points:
    63
    Ratings:
    +115
    soi have been offered one for around £600 reckon its worth goin for?
     
  8. jgrg

    jgrg
    Active Member

    Joined:
    Oct 19, 2004
    Messages:
    547
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    28
    Location:
    Cambridge
    Ratings:
    +33
    Is that an "IScan HD" or "IScan HD+"? It is a good price for the HD, and a superb price for an HD+. There are some reduced price HD models around now that the HD+ is about to be available. (The HD+ adds the ability to scale HDCP sources from the DVI input and transmit them on the DVI output.)

    James
     
  9. Yaka

    Yaka
    Active Member

    Joined:
    Dec 20, 2000
    Messages:
    1,682
    Products Owned:
    2
    Products Wanted:
    0
    Trophy Points:
    63
    Ratings:
    +115
    its the HD+ me dads mate used it with his kit, but is selling his stuff off due to divorce. idont have the sharp tv yet dunno if empire direct do really have it in stockt so i cant test it.

    as for me dads mate, so clue less about it he is he dont know what it is realy
     

Share This Page

Loading...